Allowance for Loan Losses and Credit Quality (Allowance for Loan Losses Activity) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	$ 7,550	$ 7,494	$ 7,302	$ 7,560	$ 7,494	$ 7,560
Provision (Credit) charged to operations	150	150	(100)	(200)	300	(300)
Loans charged off	0	(101)	(101)	(60)
Recoveries of loans charged off	7	7	381	2
Ending Balance	7,707	7,550	7,482	7,302	7,707	7,482
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	1,370	1,204	981	1,025	1,204	1,025
Provision (Credit) charged to operations	85	166	(6)	(44)
Loans charged off	0	0	0	0
Recoveries of loans charged off	0	0	0	0
Ending Balance	1,455	1,370	975	981	1,455	975
Commercial Portfolio Segment [Member] \| Commercial Business [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	1,822	1,732	1,348	2,005	1,732	2,005
Provision (Credit) charged to operations	(386)	88	(284)	(657)
Loans charged off	0	0	(101)	0
Recoveries of loans charged off	1	2	1	0
Ending Balance	1,437	1,822	964	1,348	1,437	964
Commercial Portfolio Segment [Member] \| Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	2,634	2,574	3,300	3,049	2,574	3,049
Provision (Credit) charged to operations	352	56	(263)	311
Loans charged off	0	0	0	(60)
Recoveries of loans charged off	5	4	378	0
Ending Balance	2,991	2,634	3,415	3,300	2,991	3,415
Commercial Portfolio Segment [Member] \| Mortgage Warehouse Lines [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	642	973	867	866	973	866
Provision (Credit) charged to operations	260	(331)	323	1
Loans charged off	0	0	0	0
Recoveries of loans charged off	0	0	0	0
Ending Balance	902	642	1,190	867	902	1,190
Residential Portfolio Segment [Member] \| Residential Real Estate Loans [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	365	367	192	288	367	288
Provision (Credit) charged to operations	20	99	85	(96)
Loans charged off	0	(101)	0	0
Recoveries of loans charged off	0	0	0	0
Ending Balance	385	365	277	192	385	277
Consumer Portfolio Segment [Member] \| Loan to Individuals [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	122	112	19	109	112	109
Provision (Credit) charged to operations	(3)	9	3	(92)
Loans charged off	0	0	0	0
Recoveries of loans charged off	1	1	2	2
Ending Balance	120	122	24	19	120	24
Consumer Portfolio Segment [Member] \| Other [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	0	0	0	0	0	0
Provision (Credit) charged to operations	0	0	0	0
Loans charged off	0	0	0	0
Recoveries of loans charged off	0	0	0	0
Ending Balance	0	0	0	0	0	0
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	595	532	595	218	532	218
Provision (Credit) charged to operations	(178)	63	42	377
Loans charged off	0	0	0	0
Recoveries of loans charged off	0	0	0	0
Ending Balance	$ 417	$ 595	$ 637	$ 595	$ 417	$ 637

A valuation allowance for financing receivables that are expected to be uncollectible.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(4)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount of direct write-downs of financing receivables charged against the allowance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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